SU1298210A1 - Method for producing diphenyldisulfide - Google Patents

Abstract

The invention relates to sulphides, in particular diphenyldisulda (DPS), used in organic syntheses. An increase in the yield of DFS when processing the thiophenol concentrate NaOH and air oxidation is achieved using 2-8 wt.% Of the oxidation initiator - KU-2, with an oxidation time of 3-4 hours. The method provides an increase in the yield of DFS from 60 to 85%. 2 tab. (L with

Description

112

The invention relates to an improved process for the preparation of diphenlandyl sulfide, which is used in various organic syntheses.

The aim of the invention is to increase the yield of the product, which is achieved by using an initiator of cation-exchange resin of the type KU-2 in the amount of 2-8 wt.% For 3-4 hours during the oxidation of thiophenol with oxygen in air.

The target product is obtained from the thiophenol contained in the concentrate, formed during the processing of coal tar, the composition of the concentrate, wt.%:

Thiophenol 18,5-21,5

Phenols45,5-51, 5

WaterEverything

up to 100

The process uses cation-exchange resins of the type KU-2, obtained on the basis of copolymerisation of styrene and divinylbenzene and containing ionic groups - SO-H.

P and m, ep,. For oxidation, thiophenol is used in an amount of 2.8 kg, to which 10% NaOH solution is added in an amount of 0.6 kg to bind phenols, followed by oxidation with oxygen in the presence of oxidant - resins of cation-exchange type KU-2, oxidation is carried out for 4 hours.

The oxidation initiator is added to the reaction system in an amount of 4.0 wt.%. The process takes place at normal temperature.

After the end of the oxidation, diphenyl disulfide precipitates in an amount of 0.45 kg, which represents 90% of the thiophenol resource in water (0.5%),

A subsequent double crystal from adi diphenyl disulfide. from ethanol allows to get pic

, o glacier with melting point b1

with a total yield of 80% of the resources of thiophenol in raw materials.

Tables 1 and 2 show the data illustrating the choice of the maximum concentration of the oxidation initiator and the optimal lead time for the sand.

Table 1

25

Note. Duration of oxidation 4 hours.

T a b l i

C a

47.75

82.25

83,8

84.6

84.3

84.13

Note. Concentrates initiator reaction mixture 4%.

As can be seen from the data of table 1, the optimal concentration of initiator in the reaction medium should be considered 2-8.0 wt.%. A decrease in the latter leads to a sharp decrease in the yield of the target product; an increase in the concentration of the initiator does not lead to a noticeable increase in the yield of diphenyl disulfide.

The duration of the oxidation (Table 2) is at the level of 3-4 hours. A decrease in the oxidation time leads to a sharp decrease in the yield of diphenyl

312982

disulfide, increasing the duration of the contact does not give a noticeable increase in the yield of the target product.

Claims (1)

 The proposed method allows to increase the yield of the target product, obtained from the thiophenol concentrate, up to 85 against 60% according to a known method. The method of obtaining diphenyldisulfide by treating the concentrate with thiopheno-10 Editor G. Volkova Compiled by T.Vlasova Tehred; M.Morgental Proofreader S. Cherni Order 857/24 Circulation VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, Projecto st., 4 104 la, formed during the processing of coal tar, sodium hydroxide solution, followed by oxidation with air oxygen, 6 t that in order to increase the yield of the target product, the oxidation is carried out in the presence of a KU-2 type cation-exchange resin 2-8 wt.% Within 3-4 hours